The pilot was practicing takeoff and landings on runway 12. During the landing roll, the airplane started to drift to the right and the pilot corrected with rudder. The airplane departed the runway to the right and struck a ditch. During the impact the nose landing gear assembly and propeller were bent. The left wing struck the ground resulting in substantial damage to the left wing spar. No preaccident mechanical malfunctions or failures were reported that would have precluded normal operation.